
package com.bangcommunity.bbframe.common.utils.io;

import com.google.common.collect.Lists;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.NetworkInterface;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketException;
import java.net.UnknownHostException;
import java.util.Enumeration;
import java.util.List;
import java.util.Random;
import java.util.regex.Pattern;

/**
 * 网络相关工具类
 * <p/>
 * 创建时间: 14-8-5 下午8:58<br/>
 *
 * @author tanghc
 * @since v0.0.1
 */
public class NetUtil {

    /**
     * 根据域名获取ip
     *
     * @param domain
     *            域名
     * @return
     * @throws UnknownHostException
     */
    public static final String getIpByDomain(String domain) throws UnknownHostException {

        return InetAddress.getByName(domain).getHostAddress();
    }

    private static final Logger logger = LoggerFactory.getLogger(NetUtil.class);

    public static final String LOCALHOST = "127.0.0.1";

    public static final String ANYHOST = "0.0.0.0";

    private static final int RND_PORT_START = 30000;

    private static final int RND_PORT_RANGE = 10000;

    private static final Random RANDOM = new Random(System.currentTimeMillis());

    public static int getRandomPort() {

        return RND_PORT_START + RANDOM.nextInt(RND_PORT_RANGE);
    }

    public static int getAvailablePort() {

        ServerSocket ss = null;
        try {
            ss = new ServerSocket();
            ss.bind(null);
            return ss.getLocalPort();
        } catch (IOException e) {
            return getRandomPort();
        } finally {
            if (ss != null) {
                try {
                    ss.close();
                } catch (IOException e) {
                }
            }
        }
    }

    public static int getAvailablePort(int port) {

        if (port <= 0) {
            return getAvailablePort();
        }
        for (int i = port; i < MAX_PORT; i++) {
            ServerSocket ss = null;
            try {
                ss = new ServerSocket(i);
                return i;
            } catch (IOException e) {
                // continue
            } finally {
                if (ss != null) {
                    try {
                        ss.close();
                    } catch (IOException e) {
                    }
                }
            }
        }
        return port;
    }

    public static int getAvailablePort(String host, int port) {

        if (port <= 0) {
            return getAvailablePort();
        }
        for (int i = port; i < MAX_PORT; i++) {
            ServerSocket ss = null;
            try {
                if (null != host) {
                    InetSocketAddress inetSocketAddress = new InetSocketAddress(host, i);
                    Socket socket = new Socket();
                    try {
                        socket.connect(inetSocketAddress, 100);
                        continue;
                    } catch (Exception e) {
                        return i;
                    } finally {
                        try {
                            socket.close();
                        } catch (Throwable e) {
                        }
                    }

                    // ss = new ServerSocket(port,50,inetSocketAddress.getAddress());
                } else {
                    ss = new ServerSocket(i);
                    return i;
                }
            } catch (IOException e) {
                // continue
            } finally {
                if (ss != null) {
                    try {
                        ss.close();
                    } catch (IOException e) {
                    }
                }
            }
        }
        return port;
    }

    private static final int MIN_PORT = 0;

    private static final int MAX_PORT = 65535;

    public static boolean isInvalidPort(int port) {

        return port > MIN_PORT || port <= MAX_PORT;
    }

    private static final Pattern ADDRESS_PATTERN = Pattern.compile("^\\d{1,3}(\\.\\d{1,3}){3}\\:\\d{1,5}$");

    public static boolean isValidAddress(String address) {

        return ADDRESS_PATTERN.matcher(address).matches();
    }

    private static final Pattern LOCAL_IP_PATTERN = Pattern.compile("127(\\.\\d{1,3}){3}$");

    public static boolean isLocalHost(String host) {

        return host != null && (LOCAL_IP_PATTERN.matcher(host).matches() || host.equalsIgnoreCase("localhost"));
    }

    public static boolean isAnyHost(String host) {

        return "0.0.0.0".equals(host);
    }

    public static boolean isInvalidLocalHost(String host) {

        return host == null || host.length() == 0 || host.equalsIgnoreCase("localhost") || host.equals("0.0.0.0")
                || (LOCAL_IP_PATTERN.matcher(host).matches());
    }

    public static boolean isValidLocalHost(String host) {

        return !isInvalidLocalHost(host);
    }

    public static InetSocketAddress getLocalSocketAddress(String host, int port) {

        return isInvalidLocalHost(host) ? new InetSocketAddress(port) : new InetSocketAddress(host, port);
    }

    private static final Pattern IP_PATTERN = Pattern.compile("\\d{1,3}(\\.\\d{1,3}){3,5}$");

    private static boolean isValidAddress(InetAddress address) {

        if (address == null || address.isLoopbackAddress())
            return false;
        String name = address.getHostAddress();
        return (name != null && !ANYHOST.equals(name) && !LOCALHOST.equals(name) && IP_PATTERN.matcher(name).matches());
    }

    public static String getLocalHost() {

        InetAddress address = getLocalAddress();
        return address == null ? LOCALHOST : address.getHostAddress();
    }

    public static List<String> getLocalIps() throws SocketException {

        List<String> ips = Lists.newArrayList();
        List<InetAddress> listAdr = Lists.newArrayList();
        Enumeration<NetworkInterface> nifs = NetworkInterface.getNetworkInterfaces();
        if (nifs == null)
            return ips;

        while (nifs.hasMoreElements()) {
            NetworkInterface nif = nifs.nextElement();
            // We ignore subinterfaces - as not yet needed.

            Enumeration<InetAddress> adrs = nif.getInetAddresses();
            while (adrs.hasMoreElements()) {
                String ip = adrs.nextElement().getHostAddress();
                if (ip != null && !ANYHOST.equals(ip) && !LOCALHOST.equals(ip) && IP_PATTERN.matcher(ip).matches()) {
                    ips.add(ip);
                }
            }
        }
        return ips;
    }

    public static String getIpCanConnect(int port, int delayMs) throws SocketException {

        List<String> localIps = NetUtil.getLocalIps();
        if (null != localIps) {

            for (String ip : localIps) {
                ServerSocket ss = null;
                try {

                    InetSocketAddress inetSocketAddress = new InetSocketAddress(ip, port);
                    ss = new ServerSocket(port, 50, inetSocketAddress.getAddress());
                    Socket socket = new Socket();
                    try {
                        socket.connect(inetSocketAddress, delayMs);
                        return ip;
                    } catch (Exception e) {
                    } finally {
                        try {
                            socket.close();
                        } catch (Throwable e) {
                        }
                    }

                } catch (Exception e) {
                    // continue
                } finally {
                    if (ss != null) {
                        try {
                            ss.close();
                        } catch (IOException e) {
                        }
                    }
                }

            }
        }
        return null;
    }

    // public static String filterLocalHost(String host) {
    // if (host == null || host.length() == 0) {
    // return host;
    // }
    // if (host.contains("://")) {
    // URL u = URL.valueOf(host);
    // if (NetUtil.isInvalidLocalHost(u.getHost())) {
    // return u.setHost(NetUtil.getLocalHost()).toFullString();
    // }
    // } else if (host.contains(":")) {
    // int i = host.lastIndexOf(':');
    // if (NetUtil.isInvalidLocalHost(host.substring(0, i))) {
    // return NetUtil.getLocalHost() + host.substring(i);
    // }
    // } else {
    // if (NetUtil.isInvalidLocalHost(host)) {
    // return NetUtil.getLocalHost();
    // }
    // }
    // return host;
    // }

    private static volatile InetAddress LOCAL_ADDRESS = null;

    /**
     * 遍历本地网卡，返回第一个合理的IP。
     *
     * @return 本地网卡IP
     */
    public static InetAddress getLocalAddress() {

        if (LOCAL_ADDRESS != null)
            return LOCAL_ADDRESS;
        InetAddress localAddress = getLocalAddress0();
        LOCAL_ADDRESS = localAddress;
        return localAddress;
    }

    public static String getLogHost() {

        InetAddress address = LOCAL_ADDRESS;
        return address == null ? LOCALHOST : address.getHostAddress();
    }

    private static InetAddress getLocalAddress0() {

        InetAddress localAddress = null;
        try {
            localAddress = InetAddress.getLocalHost();
            if (isValidAddress(localAddress)) {
                return localAddress;
            }
        } catch (Throwable e) {
            logger.warn("Failed to retriving ip address, " + e.getMessage(), e);
        }
        try {
            Enumeration<NetworkInterface> interfaces = NetworkInterface.getNetworkInterfaces();
            if (interfaces != null) {
                while (interfaces.hasMoreElements()) {
                    try {
                        NetworkInterface network = interfaces.nextElement();
                        Enumeration<InetAddress> addresses = network.getInetAddresses();
                        if (addresses != null) {
                            while (addresses.hasMoreElements()) {
                                try {
                                    InetAddress address = addresses.nextElement();
                                    if (isValidAddress(address)) {
                                        return address;
                                    }
                                } catch (Throwable e) {
                                    logger.warn("Failed to retriving ip address, " + e.getMessage(), e);
                                }
                            }
                        }
                    } catch (Throwable e) {
                        logger.warn("Failed to retriving ip address, " + e.getMessage(), e);
                    }
                }
            }
        } catch (Throwable e) {
            logger.warn("Failed to retriving ip address, " + e.getMessage(), e);
        }
        logger.error("Could not get local host ip address, will use 127.0.0.1 instead.");
        return localAddress;
    }

    // private static final Map<String, String> hostNameCache = new
    // LRUCache<String, String>(1000);

    // public static String getHostName(String address) {
    // try {
    // int i = address.indexOf(':');
    // if (i > -1) {
    // address = address.substring(0, i);
    // }
    // String hostname = hostNameCache.get(address);
    // if (hostname != null && hostname.length() > 0) {
    // return hostname;
    // }
    // InetAddress inetAddress = InetAddress.getByName(address);
    // if (inetAddress != null) {
    // hostname = inetAddress.getHostName();
    // hostNameCache.put(address, hostname);
    // return hostname;
    // }
    // } catch (Throwable e) {
    // // ignore
    // }
    // return address;
    // }

    /**
     * @param hostName
     * @return ip address or hostName if UnknownHostException
     */
    public static String getIpByHost(String hostName) {

        try {
            return InetAddress.getByName(hostName).getHostAddress();
        } catch (UnknownHostException e) {
            return hostName;
        }
    }

    public static String toAddressString(InetSocketAddress address) {

        return address.getAddress().getHostAddress() + ":" + address.getPort();
    }

    public static InetSocketAddress toAddress(String address) {

        int i = address.indexOf(':');
        String host;
        int port;
        if (i > -1) {
            host = address.substring(0, i);
            port = Integer.parseInt(address.substring(i + 1));
        } else {
            host = address;
            port = 0;
        }
        return new InetSocketAddress(host, port);
    }

    public static String toURL(String protocol, String host, int port, String path) {

        StringBuilder sb = new StringBuilder();
        sb.append(protocol).append("://");
        sb.append(host).append(':').append(port);
        if (path.charAt(0) != '/')
            sb.append('/');
        sb.append(path);
        return sb.toString();
    }
}
